Problem: Khan.scratchpad.disable(); Jessica sells magazine subscriptions and earns $$4$ for every new subscriber she signs up. Jessica also earns a $$21$ weekly bonus regardless of how many magazine subscriptions she sells. If Jessica wants to earn at least $$58$ this week, what is the minimum number of subscriptions she needs to sell?
Explanation: To solve this, let's set up an expression to show how much money Jessica will make. Amount earned this week $=$ $ $ Subscriptions sold $\times$ Price per subscription $+$ Weekly bonus Since Jessica wants to make at least $$58$ this week, we can turn this into an inequality. Amount earned this week $\geq $58$ Subscriptions sold $\times$ Price per subscription $+$ Weekly bonus $\geq $58$ We are solving for the number of subscriptions sold, so let subscriptions sold be represented by the variable $x$ We can now plug in: $x \cdot $4 + $21 \geq $58$ $ x \cdot $4 \geq $58 - $21 $ $ x \cdot $4 \geq $37 $ $x \geq \dfrac{37}{4} \approx 9.25$ Since Jessica cannot sell parts of subscriptions, we round $9.25$ up to $10$ Jessica must sell at least 10 subscriptions this week.